Sigma Dial Rolex

The Rolex Sigma dial, first appearing in the early 1970s, is a fascinating detail collectors love—those tiny sigma symbols flanking "Swiss" at 6 o'clock quietly signaled the use of solid gold markers and hands. It's subtle, almost like a secret handshake among vintage enthusiasts, and it carries serious horological weight. At Tropical Watch, where rare and storied timepieces are the norm, the Sigma dial has its own quiet spotlight.